This invention relates to Venetian blinds, in particular, to venetian blinds that are deployed from the lower half of a window. That is, a blind that is extended upwardly toward the top of a window framework before tilting the slats to achieve full or partial privacy.
In the operation of most commercial blinds, a plurality of string ladders connected to fixed top and movable bottom horizontal units are used to provide support for slats, which when tilted, provides privacy for occupants. To achieve privacy at the lower region of a window, the bottom units of conventional blinds must be extended accordingly and all of the slats tilted to avoid a line of sight viewing from without. There have been several inventions designed to provide for partial tilting for a limited number of slats on a blind. Some of these systems are shown in U.S. Pat. No. 4,940,070 to S. L. Warden, U.S. Pat. No. 4,621,672 to Hsu and U.S. Pat. No. 2,579,485 to H. W. Fergurson et al. These systems require, in some cases, considerable modifications to existing mechanisms before they can be successfully deployed. Moreover, because of their deployment from the top of a window, they cannot provide the degree of ambient light and thermal radiation penetration afforded by the blind of this invention.
It is therefore an object of the present invention to provide an improved modification to Venetian blinds whereby the string ladders containing a plurality of slats are upwardly extended from the bottom of a window.
Another object of the present invention is to provide an improved blind that provides privacy for users from outside pedestrian traffic while permitting ambient light to enter the room from the upper portion of the window.
A still further object of this invention is to provide a low cost passive solar heating system by allowing thermal radiation to enter a room through the upper portion of a window while providing privacy for persons whose standing or sitting head height is below a certain blind extension level.
Other objectives of the invention will become obvious during the detailed description of the invention.